OF SEA-WATER IN THE DIFFERENT PARTS OF THE OCEAN. 
223 
and an under-current which carries its waters into the Atlantic. This opinion of the 
superior salinity of the Mediterranean has been completely confirmed by eleven com- 
plete analyses of water taken between the Straits of Gibraltar and the Greek Archipe- 
lago. The mean salinity of this region is 37*936, while the whole ocean contains 
34*388 per 1000 salt. Its coefficient is 1*815. Its maximum (39*257) falls between 
the Island of Candia and the African shore off the Libyan desert, as the maximum of 
the Atlantic is off the Sahara, but the mean of the Mediterranean is a little higher than 
the maximum of the Atlantic ; the whole Mediterranean is under the influence of Africa, 
and its hot and dry winds. The minimum for the Mediterranean is at the Straits of 
Gibraltar with 36*301 ; the mean salinity of the northern Atlantic Ocean between 30° 
and 40° N. lat., but more towards the west, is 36*332 (deduced from eight complete 
analyses) ; the surface-water from the Straits of Gibraltar is thus corresponding to that 
from the Atlantic of the same latitude. When entering the Straits the quantity of salt 
increases rather rapidly, and is at a short distance from them, at 4° 2' W. long., 37*014; 
between the Balearic Islands and the Spanish coast it is 38*058, and a little further on 
38*321, between the Island of Sardinia and Naples 38*654. Somewhat nearer to the 
coast of Malta it decreases to 38*541, and further on towards Greece it decreases again 
to 38*013, and would probably decrease more in the direction of the Bosphorus, but I 
have no observations from that part of the Mediterranean. From Malta to the coast of 
Africa it increases to the maximum of 39*257. 
There is another opinion generally reported, that the water of the Mediterranean 
contains a greater proportion of magnesia than the water of the ocean. This is, how- 
ever, not the case ; the mean proportion between chlorine and magnesia is for the Medi- 
terranean 100 : 10*90, and for the ocean 100 : 11*07 ; nor is there any remarkable differ- 
ence in the proportions of the other main substances. The proportion between chlorine 
and sulphuric acid is for the ocean 100 : 11*89, and for the Mediterranean 100 : 11*82 ; 
for lime it is in the ocean 100 : 2*96, and in the Mediterranean 100 : 3*08. 
Tenth Begion, A. The Black Sea and the Sea of Assov . — Like the Baltic, the Black 
Sea contains sea-water of but little strength, and the mean deduced from three observa- 
tions, of which one is from myself, the two others by M. Gobel, is 15*894, maximum 
=18*146, minimum =11*880. In my own analysis of water from the Black Sea, fifty 
English miles from the Bosphorus, I found the proportion of chlorine 100, to sulphuric 
acid 11*71, to lime 4*22, to magnesia 12*64, and thus a considerable increase in the lime 
and magnesia. 
Tenth Begion, B. The Caspian Sea . — This sea being by many geologists considered to 
have been in former times in connexion with the Black Sea, it might be of some interest to 
compare its water with that of the Black Sea. I have, however, not had opportunity 
of making an analysis of it myself, but have calculated other analyses according to my 
method. Of these five analyses four are by M. Mahner, and published by M. Baer in 
his ‘ Caspian Studies’ (Caspische Studien). As might be expected, the quantity of saline 
matter shows great differences, between 56*814 per 1000 in the Bay of Karassu or 
